Pivotally segmented device for feeding a set of wires to a robot arm

ABSTRACT

An apparatus for feeding a set of threads (25) to a feeding head at a robot arm (10) which is freely movable in the room. The apparatus comprises a first arm segment (11) which protrudes at an angle from the robot arm (10), and which is pivotally connected with an inner end to the robot arm and constitutes a carrier for a first set of thread guide loops (13). The apparatus also comprises a second arm segment (16) which is pivotally connected to a pivot point (15) at the outer end of the first arm segment (11) and which second arm segment forms a carrier for a second set of thread guide loops (13).

FIELD OF THE INVENTION

The present invention refers to an apparatus for feeding a set ofthreads to a feeding head at a robot arm which is freely movable in theroom.

BACKGROUND OF THE INVENTION

The production of fibre reinforced thermosetting plastic products can beautomatized by the use of an industrial robot, by means of which a fibrefeed apparatus can be controlled, so that precise amounts of fibres arefed out which are oriented for maximum strength, without the fibresprojecting out through the outer plastic layer of the product. Owing tothe repeatability of the robot, the quality of these products can beincreased considerably, while at the same time problems related to badwork environment and labour fatigue can be solved.

The fibre feeding apparatus is preferably located in a feedout headwhich can be mounted upon a movable robot arm. Several fibre threads aresupplied to the feedout head, which cuts the threads in suitablelengths. The feeding speed of each fibre thread can be in the range ofabout 10 meters per second.

Because of the mobility of the robot arm over a comparatively largerange of movement, the thin threads of which one or more may have theirfeeding stopped, risk rubbing against each other and getting tangled.

THE TECHNICAL PROBLEM

One object of the present invention is therefore to provide an apparatuswhich makes it possible for the robot arm to work freely, without riskfor the threads getting tangled.

THE SOLUTION

For this object, the invention is characterized in a first arm segmentwhich protrudes at an angle from the robot arm, and which is pivotallyconnected with an inner end to the robot arm and constitutes a carrierfor a first set of thread guide loops, and in a second arm segment whichis pivotally connected to a pivot point at the outer end of the firstarm segment and which second arm segment forms a carrier for a secondset of thread guide loops. Because of this arrangement of arm segmentsand thread guide loops, an efficient separation of the single threads isprovided with simple means.

DESCRIPTION OF THE DRAWINGS

The invention will be described hereinafter with reference toembodiments that are shown in the enclosed drawings, wherein

FIG. 1 shows an apparatus according to the invention in a side view, and

FIG. 2 shows the apparatus in FIG. 1 in a plane view.

DESCRIPTION OF EMBODIMENTS

In FIG. 1, the reference number 10 designates a robot arm, from which afirst arm segment 11 projects. The arm segment 11 is pivotally connectedto the robot arm 10 and constitutes an attachment for a carrier 12 withfive at distances from each other and the arm segment 11 located threadguide loops 13. The ability to pivot the arm segment 11 is illustratedby the arrow 14 in FIG. 2.

The outer end of the first arm segment 11 is provided with a pivot point15 in which a second arm segment is pivotally connected. The ability topivot the arm segment 16 is illustrated by the arrow 17 in FIG. 1. Thearm segment 16 forms an attachment for a second carrier 18 which in thesame manner as the carrier 12 is provided with five thread guide loops13. The carrier 18 is rotatable connected to the arm segment 16 which isillustrated by the arrow 19 in FIG. 2.

In a corresponding way, the outer end of the second arm segment 16 isprovided with a pivot point 20, in which a third arm segment 21 ispivotally connected. The ability to pivot the arm segment 21 isillustrated by the arrow 22 in FIG. 1. The arm segment 21 forms anattachment for a third carrier 23 which in the same manner as thecarriers 12 and 18 is provided with five thread guide loops 13. Thecarrier 23 is rotatable connected to the arm segment 21 which isillustrated by the arrow 24 in FIG. 2.

Thus, the threads 25 are pulled from different magazine bobbins, thestraight way between the thread guide loops 13 in the carriers 23, 18and 12, without crossing them and at about the same distance from therespective arm segment.

Then when the robot arm moves, the arm segments 11, 16 and 21 willchange their relative angles and adjust themselves according to thedirection of the magazine bobbins. To this, the bobbins 12, 18 and 23will automatically turn themselves around the arm segments, so that theshortest possible distance of thread line is accomplished, withouthaving the threads rubbing against each other. The thread guide loops 13may be produced from a ceramic material.

The invention is not limited to the above described embodiment, insteadmore variants are conceivable within the scoop of the following claims.For example, it is possible add more arm segments. Also, the armsegments may be flexible of a elastic material.

I claim:
 1. An apparatus for feeding a set of threads to a robot armwhich is freely movable in a room, the apparatus comprising:a first armsegment which protrudes at an angle from the robot arm, the first armsegment having a first end which is pivotally connected to the robotarm; the first arm segment having a second end a first set of threadguide loops carried on the first arm segment; a second arm segmentpivotally connected to the second end of the first arm segment; and asecond set of thread guide loops carried on the second arm segment. 2.The apparatus according to claim 1, further comprising:the second armsegment having a respective third end; a third arm segment pivotallyconnected to the third end of the second arm segment; and a third set ofthread guide loops carried on the third arm segment.
 3. The apparatusaccording to claim 1, further comprising a respective carrier for eachof the thread guide loops each guide loop is mounted in the respectivecarrier on the respective arm segment for the respective guide loop,each of the carriers is rotatable around the respective arm segment onwhich the carrier is mounted.
 4. The apparatus according to claim 1,wherein the second arm segment is pivotable about at least 90° withrespect to the first arm segment.
 5. The apparatus according to claim 1,wherein the arm segments are made of a flexible, elastic material.